A molybdenum and a tungsten isoenzyme of formylmethanofuran dehydrogenase in the thermophilic archaeon Methanobacterium wolfei.
A molybdenum and a tungsten isoenzyme of formylmethanofuran dehydrogenase in the thermophilic archaeon Methanobacterium wolfei.
复制标题
嗜热古菌沃尔氏甲烷杆菌中甲酰甲烷呋喃脱氢酶的钼和钨同工酶。
DOI：
10.1111/j.1432-1033.1992.tb17376.x
复制
发表时间：
1992
期刊：
影响因子：
--
通讯作者：
R. Thauer
中科院分区：
文献类型：
--
作者：
R. Schmitz;S. Albracht;R. Thauer
我们最近报道，嗜热古菌甲烷杆菌wolfei含有两个甲酰甲烷呋喃脱氢酶，I和II。甲酰甲烷呋喃脱氢酶II，这是优先在钨生长的细胞中表达，已被纯化，并显示是一个钨-铁-硫蛋白。我们现在已经纯化和表征甲酰基甲烷呋喃脱氢酶I从生长的细胞，并表明它是一种铁硫蛋白。纯化的酶，具有27 U/mg蛋白质的比活性，被发现由表观分子量为64 kDa，51 kDa和31 kDa的三个亚基组成，并且每mol 146-kDa分子含有约0.23 mol钼，0.46 mol异蝶呤鸟嘌呤二核苷酸和6.6 mol非血红素铁，但没有钨（< 0.01 mol）。钼酶不同于钨酶（8 U/mg），因为它催化N-糠基甲酰胺和甲酸的氧化，并被氰化物灭活。这两种酶也显着不同的最佳pH值，在表观Km的电子受体，并在色谱行为。然而，钼酶和钨酶是相似的，因为α和β亚基的N-末端氨基酸序列直到残基23都是相同的，这表明这两种蛋白质是同工酶。钼酶，作为分离，被发现显示来自钼的EPR信号，证明了同位素取代。
We have recently reported that the thermophilic archaeon Methanobacterium wolfei contains two formylmethanofuran dehydrogenases, I and II. Formylmethanofuran dehydrogenase II, which is preferentially expressed in tungsten-grown cells, has been purified and shown to be a tungsten-iron-sulfur protein. We have now purified and characterized formylmethanofuran dehydrogenase I from molybdenum-grown cells and shown that it is a molybdenum-iron-sulfur protein. The purified enzyme, with a specific activity of 27 U/mg protein, was found to be composed of three subunits of apparent molecular mass 64 kDa, 51 kDa, and 31 kDa and to contain per mol 146-kDa molecule approximately 0.23 mol molybdenum, 0.46 mol molybdopterin guanine dinucleotide, and 6.6 mol non-heme iron but no tungsten (< 0.01 mol). The molybdenum enzyme differed from the tungsten enzyme (8 U/mg) in that it catalyzed the oxidation of N-furfurylformamide and formate and was inactivated by cyanide. The two enzymes also differed significantly in the pH optimum, in the apparent Km for the electron acceptor, and in the chromatographic behaviour. The molybdenum enzyme and the tungsten enzyme were similar, however, in that the N-terminal amino acid sequences determined for the alpha and beta subunits were identical up to residue 23, indicating that the two proteins are isoenzymes. The molybdenum enzyme, as isolated, was found to display an EPR signal derived from molybdenum as evidenced by isotope substitution.
甲酰甲烷呋喃的作用：四氢甲烷蝶呤甲酰转移酶在二氧化碳产甲烷中的作用。
DOI：
--
发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Donnelly,MI;Wolfe,RS
通讯作者：
Wolfe,RS